As one will ascertain, pressure transducers capable of operating at high temperatures of at least, for example 600° C. and being physically small are highly desirous in various applications. When temperatures reach levels above 600° C., silicon-sensing networks and silicon force collectors undergo significant plastic deformation rendering the device useless as a pressure transducer. In order to overcome this problem, high temperature transducers employing SiC have been fabricated. For example, see U.S. Pat. No. 5,165,283 to A. D. Kurtz et al. entitled, “High Temperature Transducers and Methods of Fabricating Same Employing SiC” assigned to the assignee herein, Kulite Semiconductor Products, Inc. Also see, for example, U.S. Pat. No. 6,058,782 entitled, “Hermetically Sealed Ultra High Temperature SiC Pressure Transducers and Method for Fabricating the Same” issued to A. D. Kurtz et al. on May 9, 2000 and also assigned to the assignee herein. Thus, there is a desire to fabricate high temperature transducers.
The present invention enables the fabrication of a specifically selected (both the type and the doping) single crystal 3C—SiC layer located on, and dielectrically isolated from an independently selected 6H—SiC substrate, or any other SiC substrate material.
The device thus produced using this approach will have the benefit of having an excellent single crystal 3C—SiC, on an insulator layer with specified doping for piezoresistive sensing while having an independently selected substrate material like 6H—SiC or 4H—SiC used for producing the deflecting membrane or other substrate.